1 /* 2 * Copyright (C) 2014 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN 24 * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at 34 * [email protected] 35 * 36 */ 37 38 #define BTSTACK_FILE__ "gatt_browser.c" 39 40 // ***************************************************************************** 41 /* EXAMPLE_START(gatt_browser): GATT Client - Discover Primary Services 42 * 43 * @text This example shows how to use the GATT Client 44 * API to discover primary services and their characteristics of the first found 45 * device that is advertising its services. 46 * 47 * The logic is divided between the HCI and GATT client packet handlers. 48 * The HCI packet handler is responsible for finding a remote device, 49 * connecting to it, and for starting the first GATT client query. 50 * Then, the GATT client packet handler receives all primary services and 51 * requests the characteristics of the last one to keep the example short. 52 * 53 */ 54 // ***************************************************************************** 55 56 #include <stdint.h> 57 #include <stdio.h> 58 #include <stdlib.h> 59 #include <string.h> 60 61 #include "btstack.h" 62 63 // gatt_browser.gatt contains the declaration of the provided GATT Services + Characteristics 64 // gatt_browser.h contains the binary representation of gatt_browser.gatt 65 // it is generated by the build system by calling: $BTSTACK_ROOT/tool/compile_gatt.py gatt_browser.gatt gatt_browser.h 66 // it needs to be regenerated when the GATT Database declared in gatt_browser.gatt file is modified 67 #include "gatt_browser.h" 68 69 typedef struct advertising_report { 70 uint8_t type; 71 uint8_t event_type; 72 uint8_t address_type; 73 bd_addr_t address; 74 uint8_t rssi; 75 uint8_t length; 76 const uint8_t * data; 77 } advertising_report_t; 78 79 static bd_addr_t cmdline_addr; 80 static int cmdline_addr_found = 0; 81 82 static hci_con_handle_t connection_handle; 83 static gatt_client_service_t services[40]; 84 static int service_count = 0; 85 static int service_index = 0; 86 87 static btstack_packet_callback_registration_t hci_event_callback_registration; 88 89 /* @section GATT client setup 90 * 91 * @text In the setup phase, a GATT client must register the HCI and GATT client 92 * packet handlers, as shown in Listing GATTClientSetup. 93 * Additionally, the security manager can be setup, if signed writes, or 94 * encrypted, or authenticated connection are required, to access the 95 * characteristics, as explained in Section on [SMP](../protocols/#sec:smpProtocols). 96 */ 97 98 /* LISTING_START(GATTClientSetup): Setting up GATT client */ 99 100 // Handles connect, disconnect, and advertising report events, 101 // starts the GATT client, and sends the first query. 102 static void handle_hci_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); 103 104 // Handles GATT client query results, sends queries and the 105 // GAP disconnect command when the querying is done. 106 static void handle_gatt_client_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); 107 108 static void gatt_client_setup(void){ 109 110 // Initialize L2CAP and register HCI event handler 111 l2cap_init(); 112 113 // Initialize GATT client 114 gatt_client_init(); 115 116 // Optinoally, Setup security manager 117 sm_init(); 118 sm_set_io_capabilities(IO_CAPABILITY_NO_INPUT_NO_OUTPUT); 119 120 // register for HCI events 121 hci_event_callback_registration.callback = &handle_hci_event; 122 hci_add_event_handler(&hci_event_callback_registration); 123 } 124 /* LISTING_END */ 125 126 static void printUUID(uint8_t * uuid128, uint16_t uuid16){ 127 if (uuid16){ 128 printf("%04x",uuid16); 129 } else { 130 printf("%s", uuid128_to_str(uuid128)); 131 } 132 } 133 134 static void dump_advertising_report(advertising_report_t * e){ 135 printf(" * adv. event: evt-type %u, addr-type %u, addr %s, rssi %u, length adv %u, data: ", e->event_type, 136 e->address_type, bd_addr_to_str(e->address), e->rssi, e->length); 137 printf_hexdump(e->data, e->length); 138 139 } 140 141 static void dump_characteristic(gatt_client_characteristic_t * characteristic){ 142 printf(" * characteristic: [0x%04x-0x%04x-0x%04x], properties 0x%02x, uuid ", 143 characteristic->start_handle, characteristic->value_handle, characteristic->end_handle, characteristic->properties); 144 printUUID(characteristic->uuid128, characteristic->uuid16); 145 printf("\n"); 146 } 147 148 static void dump_service(gatt_client_service_t * service){ 149 printf(" * service: [0x%04x-0x%04x], uuid ", service->start_group_handle, service->end_group_handle); 150 printUUID(service->uuid128, service->uuid16); 151 printf("\n"); 152 } 153 154 static void fill_advertising_report_from_packet(advertising_report_t * report, uint8_t *packet){ 155 gap_event_advertising_report_get_address(packet, report->address); 156 report->event_type = gap_event_advertising_report_get_advertising_event_type(packet); 157 report->address_type = gap_event_advertising_report_get_address_type(packet); 158 report->rssi = gap_event_advertising_report_get_rssi(packet); 159 report->length = gap_event_advertising_report_get_data_length(packet); 160 report->data = gap_event_advertising_report_get_data(packet); 161 } 162 163 /* @section HCI packet handler 164 * 165 * @text The HCI packet handler has to start the scanning, 166 * to find the first advertising device, to stop scanning, to connect 167 * to and later to disconnect from it, to start the GATT client upon 168 * the connection is completed, and to send the first query - in this 169 * case the gatt_client_discover_primary_services() is called, see 170 * Listing GATTBrowserHCIPacketHandler. 171 */ 172 173 /* LISTING_START(GATTBrowserHCIPacketHandler): Connecting and disconnecting from the GATT client */ 174 static void handle_hci_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 175 UNUSED(channel); 176 UNUSED(size); 177 178 if (packet_type != HCI_EVENT_PACKET) return; 179 advertising_report_t report; 180 181 uint8_t event = hci_event_packet_get_type(packet); 182 switch (event) { 183 case BTSTACK_EVENT_STATE: 184 // BTstack activated, get started 185 if (btstack_event_state_get_state(packet) != HCI_STATE_WORKING) break; 186 if (cmdline_addr_found){ 187 printf("Trying to connect to %s\n", bd_addr_to_str(cmdline_addr)); 188 gap_connect(cmdline_addr, 0); 189 break; 190 } 191 printf("BTstack activated, start scanning!\n"); 192 gap_set_scan_parameters(0,0x0030, 0x0030); 193 gap_start_scan(); 194 break; 195 case GAP_EVENT_ADVERTISING_REPORT: 196 fill_advertising_report_from_packet(&report, packet); 197 dump_advertising_report(&report); 198 199 // stop scanning, and connect to the device 200 gap_stop_scan(); 201 gap_connect(report.address,report.address_type); 202 break; 203 case HCI_EVENT_META_GAP: 204 // wait for connection complete 205 if (hci_event_gap_meta_get_subevent_code(packet) != GAP_SUBEVENT_LE_CONNECTION_COMPLETE) break; 206 printf("\nGATT browser - CONNECTED\n"); 207 connection_handle = gap_subevent_le_connection_complete_get_connection_handle(packet); 208 // query primary services 209 gatt_client_discover_primary_services(handle_gatt_client_event, connection_handle); 210 break; 211 case HCI_EVENT_DISCONNECTION_COMPLETE: 212 printf("\nGATT browser - DISCONNECTED\n"); 213 break; 214 default: 215 break; 216 } 217 } 218 /* LISTING_END */ 219 220 /* @section GATT Client event handler 221 * 222 * @text Query results and further queries are handled by the GATT client packet 223 * handler, as shown in Listing GATTBrowserQueryHandler. Here, upon 224 * receiving the primary services, the 225 * gatt_client_discover_characteristics_for_service() query for the last 226 * received service is sent. After receiving the characteristics for the service, 227 * gap_disconnect is called to terminate the connection. Upon 228 * disconnect, the HCI packet handler receives the disconnect complete event. 229 */ 230 231 /* LISTING_START(GATTBrowserQueryHandler): Handling of the GATT client queries */ 232 233 static void handle_gatt_client_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 234 UNUSED(packet_type); 235 UNUSED(channel); 236 UNUSED(size); 237 238 gatt_client_service_t service; 239 gatt_client_characteristic_t characteristic; 240 switch(hci_event_packet_get_type(packet)){ 241 case GATT_EVENT_SERVICE_QUERY_RESULT: 242 gatt_event_service_query_result_get_service(packet, &service); 243 dump_service(&service); 244 services[service_count++] = service; 245 break; 246 case GATT_EVENT_CHARACTERISTIC_QUERY_RESULT: 247 gatt_event_characteristic_query_result_get_characteristic(packet, &characteristic); 248 dump_characteristic(&characteristic); 249 break; 250 case GATT_EVENT_QUERY_COMPLETE: 251 // GATT_EVENT_QUERY_COMPLETE of search characteristics 252 if (service_index < service_count) { 253 service = services[service_index++]; 254 printf("\nGATT browser - CHARACTERISTIC for SERVICE %s, [0x%04x-0x%04x]\n", 255 uuid128_to_str(service.uuid128), service.start_group_handle, service.end_group_handle); 256 gatt_client_discover_characteristics_for_service(handle_gatt_client_event, connection_handle, &service); 257 break; 258 } 259 service_index = 0; 260 break; 261 default: 262 break; 263 } 264 } 265 /* LISTING_END */ 266 267 int btstack_main(int argc, const char * argv[]); 268 int btstack_main(int argc, const char * argv[]){ 269 270 #ifdef HAVE_BTSTACK_STDIN 271 // process command line arguments when running in a shell 272 int arg = 1; 273 cmdline_addr_found = 0; 274 275 while (arg < argc) { 276 if(!strcmp(argv[arg], "-a") || !strcmp(argv[arg], "--address")){ 277 arg++; 278 cmdline_addr_found = sscanf_bd_addr(argv[arg], cmdline_addr); 279 arg++; 280 continue; 281 } 282 fprintf(stderr, "\nUsage: %s [-a|--address aa:bb:cc:dd:ee:ff]\n", argv[0]); 283 fprintf(stderr, "If no argument is provided, GATT browser will start scanning and connect to the first found device.\nTo connect to a specific device use argument [-a].\n\n"); 284 return 0; 285 } 286 #else 287 (void)argc; 288 (void)argv; 289 #endif 290 291 // setup GATT client 292 gatt_client_setup(); 293 294 // setup ATT server - only needed if LE Peripheral does ATT queries on its own, e.g. Android and iOS 295 att_server_init(profile_data, NULL, NULL); 296 297 // turn on! 298 hci_power_control(HCI_POWER_ON); 299 300 return 0; 301 } 302 303 /* EXAMPLE_END */ 304 305 306